Reciprocating marking stamp with removable printing element



Nov. 24, 1964 w. c. HARRIS ETAL 3,158,094

RECIPROCATING MARKING STAMP WITH REMOVABLE PRINTING ELEMENT Filed March27, 1965 Via H6. 2

INVENTORS, /l/A/PL CEO/MEAL MLL/AM c? Maze/5 United States Patent3,158,094 RECIPROCATING MARKING STAMP WITH REMOVABLE PRINTING ELEMENTWilliam C. Harris and Phiiip L. Crowell, Racine, Wis, assignors to S. C.Johnson 8; Son, Inc, Racine, Wis. Fiied Mar. 27, 1963, Ser. No. 263,286Claims. (Cl. 101-327) This invention relates to a novel marking device.More I ployed devices comprise a replaceable handle for attachment toany one of a number of suitably inscribed stamps. In operation, thehandle is attached to a particular stamp, the articles to be markedsuitably inscribed, and thereafter, the handle removed and attached toother stamps as needed.

The aforesaid devices, while fulfilling a definite need, are notapplicable in operations where one stamp carrying a designated number,letter or combination of letters and numbers, is to be used over andover again at spaced intervals, as for example, where an inspector ofmaterials aifixes his designated number or letter to each piece of goodsafter it has been inspected. Preferably, if not necessarily, devicessuitable for the above type of operation must be small, compact and havea retractable marking surface to avoid having the inked surface come incontact with a working surface, leaving unwanted marks, ink smudges,etc. The available devices meeting this requirement comprise a number ofcomponents, are expensive and require a mechanical operation, therebyenhancing the chances of failure of the device.

Accordingly, it is an object of the instant invention to provide amarking stamp which is compact and easily interchanged upon a commonhandle, permitting the convenient marking of a large number of articles.

It is another object of the instant invention to provide a marking stampwhich is simple in construction, but possesses a retractable markingsurface.

It is still another object of the invention to provide a retractablehand stamp which comprises a minimum number of parts and is completelyfree of mechanically moving parts.

It is still another object of the instant invention to provide aretractable hand stamp which can be conveniently attached to a pencil.

These and other objects will become more fully apparent from thefollowing detailed description with particular emphasis being placedupon the drawing.

In general, the objects of the instant invention are accomplished byconstructing a marking stamp comprising as essential components: (a) anink retaining pad suitably inscribed on one surface, (b) a small cup forreceiving the ink retaining pad and (c) a larger cup having a shankwhich is adapted to receive a suitable handle, such as a pencil orsimilar device. The smaller cup, after being fixedly secured to the inkretaining pad, is mounted within the larger cup. The larger cup,composed of plastic or light metal, possesses a flexible shoulderimmediately adjacent the handle receiving shank. When the shank isdepressed by means of force applied to the handle, the shoulder flexesdownwardly bringing the smaller cup carrying the inscribed ink retainingmaterial into contact with the surface to be marked, leaving 3,158,094Patented Nov. 24, 1964 ice an imprint. When the force on the handle isreleased, the shank returns to its original position, retracting thesmall cup and inscribed ink retaining material Within the larger cup.The design permits a minimum number of components in the marking stamp,simplifying construction ond reducing costs.

In the accompanying drawing, forming a material part of this applicationand wherein like numerals are employed to designate like partsthroughout the specification:

FIGURE 1 is an exploded front view of the stamping mechanism, partly incross-section, the handle not being shown;

FIGURE 2 is a cross-sectional top view taken along lines 22 of FIGURE 1;

FIGURE 3 is a view looking into cup 1 along vertical line 1a of FIGURE1;

FIGURE 4 is a side elevation of the complete marking device in theretracted position, the internal components being shown in broken lines;and

FIGURE 5 is a side elevation of the device of FIGURE 4 in a depressedposition.

More specifically, refer-ring to FIGURE 1, 1 defines the large cup andshank and'2 defines the smaller cup for receiving the inscribed inkretaining pad 3. Cup and shank 1 comprises cupped portion 11, havingflexible shoulder portion 12 joining shank portion 13. Shank 13 has ahollow bore 14 for receiving a suitable handle, preferably a pencil. Thebore contains a seriesof vertical ribs 14a, seen more clearly in FIGURE2, to maintain snug contact between the shank and handle. In theembodiment shown in the drawing, a bore of smaller diameter 15, havingwalls 15a and base 15b, meets larger bore 14. The handle will rest onshoulder 150. As is apparent, it is not completely necessary to havesmall bore 15 in the structure. However, bore 15 simplifies moldingoperations and provides improved flexibility.

The smaller cup 2 is received by opening 16 of cup portion 11. Cupportion 11 contains vertical ribs 16a to help position smaller cup 2within the larger cup. In the drawing, cup 2 is held in lockingengagement with cup and shank 1 by annular channels 17, which receivescollar 20 of cup 2. Collar 20 has an annular ridge 20a which engagesannular channel 17a. Proper positioning of cup 2 in annular channel 17is enhanced by means of splines 21 on collar 20. The above arrangementsecurely locks smaller cup 2 into the larger cup and shank 1.

Ink retaining pad 3, suitably inscribed at surface 31,

is fixedly secured into opening 22 of cup 2 with an adhesive or othersuitable means. Although pad 3 can be formed of any ink retainingmaterial such as felt or microporous rubber, it is preferred that thepad be constructed from a never-inking plastic such as Porlon, trademarkof S. C. Johnson & Son, Inc. Porlon is a mioroporous, thermoplasicsynthetic resin composition. Thus, the Porlon pad is formed by combininga resin such as polyvinyl chloride with a plasticizer or stabilizer toform a paste or plastisol. Thereafter, the inking material, as well as avehicle therefor, are added to the paste or plastisol and thoroughlymixed. The mixture is poured into a suitable stamp mold and heated at atemperature in the range of from about 250-350" for a period of fromabout 1030 minutes. The resultant structure is a microreticulatedmaterial having the inking fluid permanently retained. Thus, the inkcannot be removed by immersing in water or other solvent. However, alight pressure contacting the stamp with the surface to be marked willleave an imprint. A stamp pad formed in this manner can make up to about50,000 impressions before the ink is exhausted. The above materials aremore completely described in Harry R. Leeds US. Patent Nos. 2,777,824and 3,055,297.

In construction of the novel stamps, components 1 and 2 are molded fromplastic or metal in a simple operation. Thus, plastic such aspolyethylene or polypropylene are eminently suitable for cup andshank 1. It has been found, however, that a more solvent resistantplastic material such as the polycarbonate resins are particularlysuitable for cup 2, since the polycarbonate resins are not detrimentallyaffected by inks or solvents which may be contained in the ink retainingpad. As is apparent, a light metal can be employed in place of theplastic. However, plastic is preferred due to cost consideration.

Although it is not strictly necessary, to prolong the life of the unit,it is desirable to increase the thickness of the plastic or metalshoulder at 12a. Thus, the enlarged radius will permit a greater numberof fiexings without having the shank tear away from the shoulder.Moreover, to provide superior flexibility, it is preferred that shoulderportion 12 contain a re-enforcing rib-like network 121), as shownclearly in FIGURE 3. As is apparent, excellent flexing of the shoulderis obtained without substantially weakening the component.

The operation of the stamping device is illustrated in FIGURE 1 andFIGURES 4 and 5 by means of the broken lines. Thus, a pencil or othersuitable handle 4 is positioned in splined shaft 13. In the retracted orreposed position, ink pad 3 andcup 2 are completely withdrawn into cup11. However, when downward pressure is applied to the handle, theshoulder portion 12 flexes, causing the inscribed surface of the ink pad31 to contact the work surface 5, leaving an imprint. When the pressureon the handle is released, the shoulder and shank assume their naturalposition, withdrawing the ink pad from the work surface. To simplify thepositioning of the stamp on the surfaces to be marked, pointer 6 canadvantageously be molded on cup portion 11.

As is apparent, the instant marking device is extremely simple inconstruction, as well as in operation. The design can be employed insets containing a multiplicity of stamps for use with a common handle,i.e.' for use in a supermarket, or it can be used where the sameinscription is to be applied to a Work surface at spaced intervals.Since the marking surface is completely retracted when pressure is notbeing exerted on the handle, the unit can be placed in a shirt pocket,etc. in the same manner as a pencil and eraser without danger of damageto the shirt. In the preferred embodiment employing a Porlon pad, it isnot necessary to have the sometimes messy inking pad for inking thestamp.

As is apparent, therefore, the presently disclosed device has manyapplications and it should be appreciated that while only the preferredembodiment has been described, the invention is not restricted thereto.Modifications will be apparent to one skilled in the art, which comewithin the scope of the appended claims.

We claim:

1. A retractable stamping device comprising an integral unit having afirst cup and shank, said first cup comprising a body portion and adepressible shoulder portion connected to said shank, said shoulder andshank together forming the top of said first cup, said first cup andshank each having an opening with said openings being in oppositedirections, a second unit associated with said first cup comprising asecond cup opening in the same direction as said first cup having asmaller diameter and shorter height than said first cup and containingan ink retaining material fixedly secured therein, and means for lockingsaid second cup into said first cup and shank, said first cup, shank,zmd second cup having the same vertical axis, whereby said ink retainingmaterial and second cup are contained completely within said first unithaving a first cup and shank, said first cup compris ing a body portionof larger diameter than said shank, having vertical ribs coveringsubstantially the entire height of said body portion and a re-enforceddepressible shoulder portion connected to said shank, said shoulder andshank forming the top of said first cup, said shank having a hollow boreopening in a direction opposite the opening in the first cup, said borecontaining internal ribs for holding said handle in snug contact withthe shank, said first cup and shank having annular channels, a secondunit associated with said first cup comprising a second cup opening inthe same direction as said first cup and having a smaller diameter andshorter height than said first cup and containing a never-inkingmicroporous microreticulated ink pad fixedly secured therein, saidsecond cup having a collar with a'series of vertical splines and anannular ridge, said splines and annularly ridged collar being held inlocking engagement with said annular channels of said first cup andshank, said first cup, shank, and second cup having the said verticalaxis, whereby said ink retaining pad is contained completely within saidfirst cup when in a reposed position, and in contact with a workingsurface when said shank and shoulder are depressed.

References Cited by the Examiner UNITED STATES PATENTS 108,351 10/70Grosskopf 101-368 677,482 7/01 Worthington 101-333 774,675 11/04Kendrick 101-406 1,285,094 11/18 Fisher 101-379 2,142,377 1/39 Roth -382,414,895 1/47 Reynolds et a1 101-327 X 2,966,116 12/60 Harris et a1101-405 X 3,055,297 9/62 Leeds 101-327 EUGENE R. CAPOZIO, PrimaryExaminer.

ROBERT E. PULFREY, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,158,094 November 24, 1964 William C. Harris et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 2, lines 53, 54 and 55, and column 3, line 46, for "Porlon", eachoccurrence, read Porelon column 3, line 18 and column 4, line 26, for"re-enforcing", each occurrence, read reinforcing Signed and sealed this13th day of April 1965,

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attcsting Officer Commissioner ofPatents

1. A RETRACTABLE STAMPING DEVICE COMPRISING AN INTEGRAL UNIT HAVING AFIRST CUP AND SHANK, SAID FIRST CUP COMPRISING A BODY PORTION AND ADEPRESSIBLE SHOULDER PORTION CONNECTED TO SAID SHANK, SAID SHOULDER ANDSHANK TOGETHER FORMING THE TOP OF SAID FIRST CUP, SAID FIRST CUP ANDSHANK EACH HAVING AN OPENING WITH SAID OPENINGS BEING IN OPPOSITEDIRECTIONS, A SECOND UNIT ASSOCIATED WITH SAID FIRST CUP COMPRISING ASECOND CUP OPENING IN THE SAME DIRECTION AS SAID FIRST CUP HAVING ASMALLER DIAMETER AND SHORTER HEIGHT THAN SAID FIRST CUP AND CONTAININGAN INK RETAINING MATERIAL FIXEDLY SECURED THEREIN, AND MEANS FOR LOCKINGSAID SECOND CUP INTO SAID FIRST CUP AND SHANK, SAID FIRST CUP, SHANK,AND SECOND CUP HAVING THE SAME VERTICAL AXIS, WHEREBY SAID INK RETAININGMATERIAL AND SECOND CUP ARE CONTAINED COMPLETELY WITHIN SAID FIRST CUPWHEN IN A REPOSED POSITION AND IN CONTACT WITH A WORKING SURFACE WHENSAID SHANK AND SHOULDER ARE DEPRESSED.